gyrator变换全息图及其在图像加密中的应用

he gyrator transform hologram is proposed.The generation and reconstruction of the gyrator transform hologram is simulated by using the fast algorithm for computing the gyrator transform.The gyrator transform hologram based on phase-shifting digital hologram is also studied.A novel method is proposed for optical image encryption by using sinusoidal phase gratings based on the mentioned above.In this proposal method,the angle of gyrator thransform,the frequency and the rotation angle of the gratings are regarded as the encryption keys,and it applies two or more cascaded gyrator tansform systems to realized the image encryption.Thus it enhance the security of encrytion system.The simulation experiments with two cascaded systems according to phase-shifting digital hologram confirm the feasiblity ,validity and the secure performance of the proposal method.